A line that describes volume across the surface of an object or shape is called a cross-contour line. These are lines that would reflect the eye's movements of what you see around. These describes form and volume as compared to contour lines which describe edges only. These lines would help in understanding a three dimensional form in a form of 2D.
The answer is to u question is: C
Answer:
<h3>The answer is 9 kg</h3>
Explanation:
To find the mass given the force and acceleration we use the formula

where
f is the force
a is the acceleration
We have
f = 18 N
a = 2 m/s²
We have

We have the final answer as
<h3>9 kg</h3>
Hope this helps you